The invention pertains to a method for aligning a belt ply which has a middle part and triangular end pieces and which is wound onto a tire-building drum in such a way that at least certain parts of the triangular end areas extend next to each other.
The invention also pertains to a device for aligning a belt ply which has a middle part and triangular end pieces and which is wound onto a tire-building drum in such a way that at least certain parts of the triangular end areas extend next to each other.
For the production of radial tires, the standard approach is to supply the prefabricated belt plies to a tire-building drum by the use of so-called belt servers. The position of the belt server can be adjusted transversely to its transport direction. The purpose of this transverse shift in the position of the belt server is to compensate for deviations in the shape of the middle part of the belt ply from an ideal rectangular form, this shift being accomplished after at least part of the leading triangular area of the belt ply has been fixed in place in the downstream area of the transport route leading to the tire-building drum, i.e., the area located behind the belt server.
Typically what happens during this step is a so-called center regulation or edge regulation. The position at the time in question is detected by the use of optical sensors such as CCD cameras. The above-described form correction for belt plies has proven reliable in the production of tires intended for use on passenger vehicles. In the production of tires which are intended for use on trucks, however, special requirements are imposed because of the large dimensions of the belt plies. Here the previously mentioned method and the corresponding device do not always lead to optimal results.